1. Field of the Invention
This invention relates, generally, to Braille pins. More particularly, it relates to a Braille pin and a pinhole or bore construction that inhibits fouling of the Braille pin by debris or contaminants.
2. Description of the Prior Art
Braille cells typically include a plurality of solid housings of parallelepiped construction. Each housing has six (6) or eight (8) pinholes or bores formed therein. Accordingly, six (6) or eight (8) Braille pins are housed in each Braille cell. The pins are arranged in two (2) columns of three (3) or four (4) pins each.
When in repose, each pin is in a retracted position where it is fully positioned within the bore formed in the housing. When not in repose, the uppermost tip of each pin, known as a Braille dot, extends from the bore where it can be felt by a user.
A Braille cell assembly is a collection of Braille cells. The pins are captive within a housing and its bore. Theoretically, the housing could be made from one housing part that serves as a base part for assembling the benders (bimorphs), circuit and pins, but this is not practical. Typically, there is at least a second part called the cap. The cap is removable and can have different heights. When combined with matching different length pins, the Braille cell assembly can be fitted to various products that have different heights. The base part of the Braille cell can be mass produced and later fitted with the appropriate height cap and pin to suit the application. The removable caps and pins facilitate serviceability of the cell as well.
The Braille pins are selectively extended by actuator means to represent Braille characters. The pins often become stuck when fouled by contaminates. When fouled, they cannot be displaced up or down reliably and the value of the Braille reader of which the pins form a part is reduced.
Thus there is a need for an improved Braille pin construction that is not fouled by ordinary amounts of debris and other contaminates.
The manufacturing of Braille readers is problematic because Braille pins are small and the bores within which they fit are also small. A single Braille cell typically includes eight (8) bores for receiving pins. Thus, even a small Braille reader having twenty (20) cells will require the manual insertion of one hundred sixty (160) Braille pins into one hundred sixty (160) bores.
A need therefore exists for an improvement in Braille pins that would facilitate the assembly of Braille readers.
However, in view of the prior art considered as a whole at the time the present invention was made, it was not obvious to those of ordinary skill in this field how the identified drawbacks of the prior art could be overcome in an effective, efficient, and economical manner.